1. Field of the Invention
The present invention relates to a high intensity magnetic separator for the wet preparation of magnetizable particles of solids, in which particles of solids suspended in a carrier medium forming a slurry or sludge or guided through a magnetic field between ferromagnetic bodies, and more particularly to such a separator which has a rotor or ferromagnetic material which supports an arrangement of containers on its periphery, the containers having ferromagnetic bodies therein, and which rotates about an approximate vertical axis, and at least one magnet system fixedly arranged outside of and adjacent the rotor and having a portion of the rotor located between its magnetic poles to close the magnetic flux through the rotor and the arrangement of containers.
2. Description of the Prior Art
The prior art recognizes a variety of high intensity magnetic separators such as, for example, the so-called Jones high intensity separator which is described in the publication "HUMBOLDT manufactures the JONES High Intensity Wet Magnetic Separator", published in English, West Germany, July, 1971, this publication being fully incorporated herein by this reference.
Briefly, the primary feature of the continuously operating Jones separator is the provision of one or two weak magnetic disc-shaped rotors having a diameter up to about 4 m and a thickness of about 20 cm which rotate between the poles of large electromagnets. The poles have the same thickness as the rotors and include in their width, in each case, about one-fourth of the periphery of the rotor.
The two rotors are located with respect to one another on the same vertical axis. On the periphery of the rotors is a number of boxes or containers in which grooved pole plates of weak magnetic material are located, which plates may be held at spacing of 0.5 to 3 mm peak spacing. The boxes are charged from above with a slurry which discharges again at the lower rim and is collected. The activity takes place in the magnetic field. In this connection, the magnetic particles adhere together with a small part of non-magnetic particles. The latter is washed out while still in the magnetic field by means of a rinsing operation and is collected separately as middlings.
The magnetic material (concentrate) is washed out of the magnetic field by means of a powerful stream of water in a neutral area between magnetic fields. Thereafter, the boxes are again available for refilling as they enter the next magnetic field. The mode of operation is, because of the above procedure, continuous. The largest of these separators may process, for example, up to 200 tons per hour.
Another separator has a cylindrical groove in which steel balls are located for the formation of a magnetic field gradient. The groove rotates about a vertical axis. It is enclosed at four points, offset by 90.degree. by two magnetic poles each, so that a horizontal magnetic field results. The charging of the slurry or sludge takes place in the area of the four magnetic fields. Magnetic material is retained between the balls by means of the magnetic forces and is flushed out after it has been turned out of the magnetic field together with the balls.
The charge quantity is appreciably less with the justmentioned device then with the device equipped with pole plates, because more unfavorable flow conditions are present. In addition, these unfavorable flow conditions have the disadvantages result that it is difficult to recover a clean magnetic product.
Other magnetic separators also operate in a similar manner, for example, the rapid separator having inclined rods instead of a ball filling, or a separator of the Ore Research Institute at Prague, Czechoslovakia having expanded metal. Also, it has already been suggested to use bodies in the form of cylinder sections, steel wool, etc as ferromagnetic fillers.